<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <div id="app"></div>
    <script src="../utils/js/old_version/react.development.js"></script>
    <script src="../utils/js/old_version/react-dom.development.js"></script>
    <script src="../utils/js/old_version/babel.min.js"></script>
    <script src="../utils/js/old_version/prop-types.js"></script>
    <script type="text/babel">
      class Demo extends React.Component {
        // 专人专用，每增加一个ref节点就需要创建一个容器，当前的节点就是容器里面放置的current键的值
        myRef1 = React.createRef(); // 创建一格myRef1容器
        alert1 = (e) => {
          console.log(e.currentTarget.value);
          // alert();
        };

        render() {
          return <input onBlur={this.alert1} type="text" />;
        }
      }
      ReactDOM.render(<Demo />, document.getElementById("app"));
    </script>
  </body>
</html>
